Wobble plate type pump



Oct. 20, 1964 1-. H. THOMPSON worms PLATE TYPE PUMP 4 Shets-Shegt 1'Filed Aug. 25, 1961 TDE /\fl////////// n//////// N x mo WWW v v mm M H*5 my ms B Q 3 3 Oct. 20, 1964 1-. H. THOMPSON 3,153,383

WOBBLE PLATE TYPE PUMP Filed Aug. 25, 1951 4 Sheets-Sheet 2 mmvrozm7011/ H TAOMQSO/V T. H- THOMPSON WOBBLE PLATE TYPE PUMP Oct. 20, 1964 4Sheets-Sheet 3 Filed Aug. 25, 1961 INVENTQR 7011/ H THOMPSON Oct. 20,1964 1'. H. THOMPSON 3,153,386

WOBBLE PLATE TYPE PUMP Filed Aug. 25, 1961 4 Sheets-Sheet 4 INVENTOR TOMIi THOMQSO/V United States Patent The invention has to do with wobbleplate pumps of the generally known type consisting of a housing for arotor incorporating a cluster of piston-containing cylinders disposedabout the axis of rotation of the rotor and, within the housing, awobble plate having drive connections with the pistons.

One of the primary objects of the invention is to provide a novelreorganization of certain of the major components so as to minimizerubbing speeds where the ends of the rotor abut the inner end faces ofthe housing closures, while enabling the wobble plate and its bearingsto be dimensioned to meet strength requirements more readily than isfeasible with the conventional disposition of the components. While notlimited thereto, this aspect of the invention is of particular value inconnection with high pressure pumps of the double act ing type, such asis illustrated in the drawings and described herein.

Other objects and advantagesof the invention will be apparent from thefollowing description of the drawings, in which:

FIG. 1 is a vertical longitudinal section of a pump incorporating theinvention in preferred form;

FIG. 2 is a vertical section on the line 2-2 of FIG. 1;

FIG. 3 is an end elevational View, on a reduced scale,

of the wobble plate and rotor, as seen in the direction of the arrows3.3 of FIG. 1;

FIG. 4 is an elevational view of the right hand end of the pump of FIG.1;

FIG. 5 is a sectional view, on a reduced scale, on the line 55 of FIG,1;

FIG 6 is a side elevational view of the pump of FIG. 1, partially brokenout and showing the wobble plate in phantom; and

FIG. 7 is a sectional view, on an enlarged scale, on the line 7--7 ofFIG. 1.

The pump is shown as comprising a cylindrical housing 10 having heads11, 1 2 enclosing the ends thereof and a main or drive shaft 13 to whicha rotor 14 is secured.

In this preferred form, the pump is of the double-acting type and therotor shown as consisting of enlarged end portions 18, 19 suitablyconnected by a reduced neck portion 29, the rotor end portionsincorporating clusters of aligned cylinders 21, 22 in which are mountedpiston members generally designated 23. The central portion of eachpiston member i exposed to the interior of the barrel. In this instanceand as is preferred, the piston members comprise piston portions 27, 28united by connecting rods 29 disposed about the reduced portion of therotor.

Centrally located within the housing is a wobble plate 30 having driveconnections with all of the piston members; and, as will be seen, thewobble plate is of annual form and encircles the piston members or,specifically, the connecting rods 29. The wobble plate consists ofrelatively rotatable inner and outer ring portions, 35, 36 andincorporates a drive ring 37 forming part of the drive connectionsbetween the wobble plate and the piston rods; and in this form, in whichthe Wobble plate encircles the piston members, the drive ring projectsradially inwards. As will be noted, it is clamped between the innerraces of the roller bearings 38 which separate the inner and outer ringportions of the wobble plate. The outer ring portion 36 of the wobbleplate is tilt-supported Patented Get. 20, 1964 by means of stub shafts39 which are journalled in the housing walls.

It will be recognized that important advantages are achieved by thisarrangement. In the first place, the wobble plate may be dimensioned topermit any desired bearing capacity, without affecting the diameter ofthe rotor; and since the wobble plate support is on the outsidethat is,between the outer ring portion and the housingthe pivot or tilt-shaftdimensions and strength may likewise be as large as necessary, againwithout affecting the dimensions of the rotor. At the same time, thediameter of the rotor, where its end faces 45, 46 are in rubbingengagement with the inner faces 47, 43 of the housing heads, can 'bekept to a minimum and the rubbing speeds thereby minimized.

Reverting to the drive connections between the wobble plate and thepiston members, the invention provides means whereby these connectionsmay be identical and of such a nature as to eliminate such variationsbetween the strokes of the piston members as may otherwise occur as theresult of centrifugal or other action. As described below, the driveconnections include bearing means carried by the connecting rods andabutting the opposite faces of the drive ring.

Each piston member (or connecting rod, in this instance) is providedwith a cylindrical recess 50 to receive the slidable and rotatablesocket member 51 of a ball and socket joint, of which the ball memberpreferably consists of two ball halves or sections 52, 53 (FIG. 7). Theinner or flat face of each ball half 52, 53 is recessed to receive asmall pilot ball 54 and all of these pilot balls are also located in acircular race or groove 55 (FIG. 5) formed in the adjacent face of thedrive ring. Pilot balls 56 are similarly located in ball sections 52 andin an identical race on the opposite face of the drive ring. By thismeans, the drive ring, ball members and socket members are allinterlocked against relative radial movement. In the result, each driveconnection follows exactlythe same path in space as every other driveconnection and, hence, each piston member partakes of the samereciprocating motion as every other piston member. It is understood, ofcourse, that while the pilot ball races are circular, the pilot ballsfollow a circular path about the axis of the drive shaft only when thewobble plate is in its fully erect position and the piston stroke zero;and that when the wobble plate is tilted and active to cause the pistonsto reciprocate in response to rotation of the drive shaft and rotor, thepilot balls follow an elliptical path in relation to the drive shaftaxis. This motion is permitted by the freedom of the socket members tomove endwise in their piston rod recesses-that is, radially, toward andfrom the drive shaft axis.

The control of the tilt of the wobble plate forms no part of the presentinvention, one of the stub shafts 39 simply being shown as extended tothe exterior of the housing to receive a handle or crank 57 (FIGS. 3, 4,6).

The inner face of at least one of the housing head members 11, 12 isformed with an openv manifold registering with the adjacent rotorcylinder ends and suchmanifold, as is common, is of circular form withappropriate interruptions located degrees apart on an axis at rightangles to the wobble plate tilt axis, to provide inlet and outletmanifold sections. Of course, in the double-acting form of pumpillustrated, both housing head members are formed with such manifolds.

Referring particularly to FIGS. 1 and 2, it will be seen that thearcuate manifolds 62, 63 formed in the inner face 47 of head member 11are separated by disc members 64, 65. These disc members are disposedand rotatable in recesses 66, 67, in the head member, with their axes orcenters offset in relation to the center line of the manifold sections.

The purpose of these discs is to facilitate the passage of solid foreignbodies from the intake to the outlet side; and in line with thatpurpose, the discs may be adapted to yield or retreat into theirrecesses in response to pressure in excess of the" normal workingpressure of the pump. As shown, the discs are backed up by springs 68,69 which are biased and normally serve to urge the discs toward theadjacent rotor end face. Thus, a piece of solid material entering theintake manifold, and thence one of the cylinders, will be expelled bythe piston of that cylinder as the rotor approaches one of the discs andthe latter will yield and, because of its offset disposition, will alsorotate and readily pass the solid to the outlet manifold section. Thecorresponding disc members and associated parts at the opposite end ofthe pump are identified by correspond primed reference characters.

It will be recognized that the same results can be accomplished bymaking the pistons yieldable in response to the excess pressuregenerated when they encounter a solid body, although in this preferredform both the discs and the pistons are shown as being yieldable. Thus,in FIG. 1, the upper piston 28, shown in section, incorporates aseparate head 70 normally sustained by spring 71.

The porting and fluid passage, arrangement form no part of the presentinvention and need not be described it being sufiicient to note that, inFIG. 4, one of the ports 75, 76 in the outer face of head member 12 willserve as the inlet and the other the outlet, depending on the directionof rotation of the rotor.

The following is claimed:

1. In a fluid handling mechanism,

a housing having a head with a face,

a circular manifold groove in said head face,

a pair of recesses in said head face 180 apart and communicating withsaid manifold,

a disc member rotatable in each said recess,

said disc members and recesses being of a diameter to intersectsaid'manifold groove and divide the same into two arcuate sections,

means biasing said disc members out of. said recesses,

the centers of said recesses and said disc members being readiallyoflset relative to said circular manifold groove, I

a rotor having a face operable against said head face and having acylinder communicating with said circular manifold groove,

a piston reciprocable in said cylinder,

a wobble plate in said housing coaxial to said manifold groove andmounted for pivotal movement around an axis transverse to the axis ofthe rotor,

and means operably connecting said wobble plate and said piston.

2. In a fluid handling mechanism,

a housing having a head With a face and a port in said face,

a rotor having an axis and a face operable against said head face andhaving a cylinder communicating with said port and oriented axially ofthe rotor,

a piston reciprocable within said cylinder,

an annular wobble plate coaxial of said head and mounted for transversepivotal movement relative to said axis of said rotor and thus transverseto said piston and cylinder,

said wobble plate carrying a radially extending relatively rotatableannular flange,

a radially extending cylindrical recess in said piston,

a cylindrical socket member axially movable in said recess,

a ball member comprising two separate ball halves each having a flatface provided with a semi-spherical recess receiving a pilot ball,

and said annular flange of said Wobble plate having a circular ball raceon each side, each sid receiving a pilot ball, I

whereby said ball and socket members are interlocked against relativeradial movement with respect to said Wobble plate but are free forcircumferential movement around the axis of the wobble plate.

3. In a fluid handling mechanism,

a housing having opposed heads each containing an annular groove port,

an integral rotor having spaced enlarged end portions connected by areduced neck,

means for turning said rotor,

each said rotor end portion including a face operable against one ofsaid heads,

each said rotor end portion including aligned cylinders communicatingwith said groove ports,

two spaced recesses spaced circumferentially around said groove,

a land in each said recess dividing each groove into an inlet sectionand an outlet section,

means biasing each land in a direction out of said recess and intoengagement with said rotor,

a piston reciprocable within each said cylinder,

an annular wobble plate coaxial to said rotor and carrying a relativelyrotatable annular flange,

and means operably connecting said Wobble plate and said piston.

References Cited in the file of this patent UNITED STATES PATENTS600,841 Oderman Mar. 15, 1898 665,448 Lapman Jan. 8, 1901 893,558Williams July 14, 1908 1,019,521 Pratt Mar. 5, 1912 1,350,551 JewellAug. 24, 1920 1,409,057 Michell Mar. 7, 1922 1,428,876 Bollinckx Sept.12, 1922 I 1,430,275 Almen Sept. 26, 1922 1,826,325 Paul Oct. 6, 19311,877,285 Eckels Sept. 13, 1932 2,168,658 Thomas Aug. 8, 1939 2,192,539Condon Mar. 5, 1940 2,388,644 Roessler Nov. 6, 1945 2,522,498 Naylor etal. Oct. 10, 1950 2,608,933 Ferris Sept. 2, 1952 3,006,324 Shaw Oct. 31,1961 FOREIGN PATENTS 533,360 Germany Apr. 29, 1930 279,933 Germany Feb.22, 1914 107,595 Great Britain June 28, 1917 357,033 Italy Feb. 26, 1938

1. IN A FLUID HANDLING MECHANISM, A HOUSING HAVING A HEAD WITH A FACE, ACIRCULAR MANIFOLD GROOVE IN SAID HEAD FACE, A PAIR OF RECESSES IN SAIDHEAD FACE 180* APART AND COMMUNICATING WITH SAID MANIFOLD, A DISC MEMBERROTATABLE IN EACH SAID RECESS, SAID DISC MEMBERS AND RECESSES BEING OF ADIAMETER TO INTERSECT SAID MANIFOLD GROOVE AND DIVIDE THE SAME INTO TWOARCUATE SECTIONS, MEANS BIASING SAID DISC MEMBERS OUT OF SAID RECESSES,THE CENTERS OF SAID RECESSES AND SAID DISC MEMBERS BEING READIALLYOFFSET RELATIVE TO SAID CIRCULAR MANIFOLD GROOVE, A ROTOR HAVING A FACEOPERABLE AGAINST SAID HEAD FACE AND HAVING A CYLINDER COMMUNICATING WITHSAID CIRCULAR MANIFOLD GROOVE, A PISTON RECIPROCABLE IN SAID CYLINDER, AWOBBLE PLATE IN SAID HOUSING COAXIAL TO SAID MANIFOLD GROOVE AND MOUNTEDFOR PIVOTAL MOVEMENT AROUND AN AXIS TRANSVERSE TO THE AXIS OF THE ROTOR,AND MEANS OPERABLY CONNECTING SAID WOBBLE PLATE AND SAID PISTON.